Device for treating a band-shaped substrate with a liquid

ABSTRACT

A device for treating a band-shaped substrate with a liquid, including: a conveying system including a winding system guiding the band-shaped substrate in a spiral path around the winding system with at least one winding; a first pulley rotatable about a first axis of rotation guiding the at least one winding of the band-shaped substrate through a first angle of deflection around part of the circumference of the first pulley, and a second pulley guiding the at least one winding of the band-shaped substrate through a second angle of deflection around part of the circumference of the second pulley, which is rotatable about a second axis of rotation, for each winding; and a bath of the liquid. The band-shaped substrate extends through the liquid over at least part of the length of the at least one winding. The second axis of rotation of each second pulley makes an angle alpha with the first axis of rotation.

The present invention relates to a device for treating a band-shaped substrate with a liquid, said device comprising a conveying system for conveying the band-shaped substrate, which conveying system comprises a winding system for guiding the band-shaped substrate in a spiral path around the winding system with at least one winding, which winding system comprises first pulley means being rotatable about a first axis of rotation for guiding said at least one winding of the band-shaped substrate through a first angle of deflection around part of the circumference of the first pulley means, and second pulley means for guiding said at least one winding of the band-shaped substrate through a second angle of deflection around part of the circumference of the second pulley means, which second pulley means comprises a second pulley, which is rotatable about a second axis of rotation, for each winding, said device further comprising a bath of the liquid, wherein the band-shaped substrate extends through the liquid in the bath over at least part of the length of said at least one winding.

German laid-open document DE 20 34 751 describes a device for plating wire. In said device, the wire is guided in a spiral path around a driving roller and a lower roller disposed below said driving roller. The driving roller is provided with a circumferential groove for each winding, whilst the lower roller comprises an independently rotatable guide wheel for each winding, which guide wheels are likewise each provided with a circumferential groove for a winding of the wire. The central axes of the driving roller and the lower roller (and thus of the guide wheels) are oriented horizontally and parallel to each other. The lower roller is disposed in a bath for a galvanic liquid. More or less as an aside it is mentioned in DE 20 34 751 that the device in question is also suitable for processing band-shaped material. An important drawback, however, is the fact that comparatively high stresses may be set up in transverse direction in the band-shaped material during the processing of band-shaped material caused by the transfer of the band-shaped substrate to a next groove within the spiral shape between the driving roller and the lower roller. Said stresses may lead to wrinkling or, even worse, to the formation of cracks in the band-shaped material, which may have a highly adverse effect on the plating process. Another drawback of the use of the known device is the fact that the device is unsuitable for plating the band-shaped substrate on one side. In fact the device is not very suitable for plating the band-shaped substrate on two sides, either, since the band-shaped substrate is treated on two sides insofar as it extends in the liquid in the bath without making contact with the lower roller, but substantially on one side, viz. the outer side, insofar as it makes contact with the lower roller in the bath. Because of said contact between the band-shaped substrate and the lower roller, the treated inner side will run the risk of being damaged, the more so because the band-shaped substrate will, for the above reasons, tend to shift over the surface of the lower roller. For a number of reasons the result will be that the layers deposited on the outer side and the inner side of the band-shaped substrate will differ from each other.

Borkowski et al “Pulley arrangement for multiple pass wire handling apparatus.” Western Electric Technical Digest, nr. 20, oktober 1970, XP002453277 xp001333208 also describes a device for treating wire which is spirally successively wound around a contact roll, sheaves of a first set of sheaves and sheaves of a second set of sheaves. The sheaves of each set of sheaves are coaxially rotatable around a common axis which skewed to the axis of rotation of the contact roll. All sheaves of each set of sheaves have different diameters.

U.S. Pat. No. 2,682,335 describes a strip handling apparatus using two cylinders having equal diameters and lengths around which a strip of material spirally is wound. The axis of one cylinder is angularly displaced relative to the axis of the other cylinder.

The object of the present invention is to provide a device as referred to in the introduction, by means of which it is possible to treat a band-shaped substrate with a liquid in a very compact manner, to which end the band-shaped substrate moves in a spiral conveying path, and wherein the stresses that occur in the band-shaped substrate are limited, so that the risk of wrinkling or cracking of the band-shaped substrate is minimised. To that end the second axis of rotation of each second pulley makes an angle α with the first axis of rotation. This leads to the very important advantage that the band-shaped substrate only needs to twist to a limited degree about its neutral line and that tensile and pressure forces occurring in the band-shaped substrate in the direction transversely to the longitudinal direction thereof will be so low that the risk of cracking and/or wrinkling will be minimal or can even be excluded altogether, depending also on the material properties and the dimensions of the band-shaped substrate. In addition to that it is possible to prevent any tendency of the band-shaped substrate to shift laterally on the first pulley means or on the second pulley means, which would lead to the longitudinal edges of the band-shaped substrate being additionally loaded, possibly causing damage to material deposited thereon by treating the band-shaped substrate with a liquid.

In order to increase the capacity the second pulley means preferably have a number of second pulleys.

The second pulleys furthermore preferably have equal diameters. This offers the advantage that very accurately angles of deflection of, for instance 180 degrees for the second pulleys in case only the winding system only comprises first pulley means and second pulley means and not any additional pulley means, such as third pulley means as in a preferred embodiment yet to be described hereinafter, can be achieved resulting in a well controlled bearing of the band-shaped substrate against the relevant pulley means. This results in a minimal mechanical load acting on the band-shaped substrate.

For reasons of constructional simplicity it is preferable if the second axes of rotation associated with the respective second pulleys extend parallel to each other. This preferred embodiment thus excludes the possibility of the second axes of rotation associated with the respective second pulleys being in line with each other, which would lead to a situation in which the guidance of the band-shaped substrate material would be sub-optimal as regards preventing internal (transverse) stresses in the band-shaped substrate.

To enhance the above advantages, it is furthermore preferable if the first pulley means has a first diameter D1 at the location where said at least one winding is guided by the first pulley means and each second pulley has a second diameter D2 at the associated location where a winding is guided by the second pulley, wherein the second diameter D2 is larger than the first diameter D1, and wherein furthermore preferably the dimension of the second diameter D2 is equal to that of the first diameter D1 divided by cos(α).

According to a very advantageous preferred embodiment, in particular assuming that the winding system only comprises first pulley means and second pulley means and not any additional pulley means, such as third pulley means as in a preferred embodiment yet to be described hereinafter, both the first angle of deflection and the second angle of deflection equal 180 degrees, since this makes it possible in a simple manner to achieve that the direction in which the band-shaped substrate approaches the second pulley means from the first pulley means is parallel to the direction in which the band-shaped substrate leaves the second pulley means in the direction of the first pulley means, albeit at the level of a next winding.

To make it possible to realise a compact construction of the device according to the invention, it is advantageous if the winding system comprises third pulley means for guiding said at least one winding of the band-shaped substrate through a third angle of deflection around part of the circumference of the third pulley means, said third pulley means comprising a third pulley for each winding, which is rotatable about a third axis of rotation, each third pulley extending parallel to an associated second pulley, wherein furthermore preferably the sum of the second angle of deflection and the third angle of deflection equals 180 degrees and/or wherein the second pulley means and the third pulley means are spaced from the first pulley means by the same distance.

Depending on the application according to the invention, it may be very advantageous if the bath is provided between the first pulley means and the second pulley means, wherein the substrate material extends rectilinearly in the bath and wherein said substrate material can be treated omnilaterally with the liquid in the bath.

Alternatively, and in particular in those cases where the band-shaped substrate is to be treated on one side only, it is advantageous if the bath extends along part of the first angle of deflection on the outer side of the first pulley means.

Precisely with a view to treating the band-shaped substrate on one side it is preferable in that regard if the first pulley means forms a mask in the bath for the side of the band-shaped substrate that faces towards the first pulley means so that the band-shaped substrate will be treated with the liquid only on the side remote from the first pulley means.

A good liquid-tight connection of the band-shaped substrate to the first pulley means can be realised in an advantageous manner if the first pulley means comprises a contact surface for each winding, which contact surface slopes upwards at the longitudinal edges of the band-shaped substrate. A proper abutment of the longitudinal edges against the upwardly sloping parts of the contact surface is ensured, to which the pressure exerted on the band-shaped substrate as a result of the liquid pressure of the liquid in the bath and the tensile stress in the band-shaped substrate contribute, so that a liquid-tight seal can be guaranteed.

In particular with a view to treating a band-shaped substrate electrochemically with a liquid, it is preferable if the first pulley means comprises a groove having a bottom and two upright edges joining said bottom for each winding, wherein the band-shaped substrate abuts against the bottom and wherein the longitudinal edges of the band-shaped substrate preferably do not make contact with the upright edges. The upright edges in turn contribute towards the homogenisation of the electrical field within which the electrochemical process takes place.

To contribute towards the homogeneity of said electrical field, a clearance of maximally 1 mm is preferably present between the longitudinal edges of the band-shaped substrate and the upright edges of the groove.

In particular if the supply of the band-shaped substrate takes place in such a manner that the transverse direction of the band-shaped substrate is oriented vertically, which is for example the case if the band-shaped substrate is unwound from a roll having a vertical axis of rotation, it is preferable if the first axis of rotation has a vertical orientation or an orientation which deviates maximally 10 degrees therefrom. An important additional advantage is that as a result of the, at least substantially, vertical orientation of the first axis of rotation, and preferably also of the second axis of rotation, the windings will extend above each other and that the spaces on the inner side or the outer side of the windings are easily accessible from the upper side for maintenance work, for example replacing anodic material in an electrolytic bath.

Alternatively it may also be very advantageous, however, if the first axis of rotation has a horizontal orientation, under which circumstances the band-shaped substrate can be guided into and out of the bath from above, so that no provisions are required for sealing the bath at the locations where the band-shaped substrate enters and leaves the bath, so that the bath can be of simple construction.

In particular in situations in which the first axis of rotation has an at least substantially vertical orientation, it is preferable if at least one passage through which the band-shaped substrate can pass is provided in at least one wall of the bath, which passage is furthermore preferably arranged for allowing the band-shaped substrate to pass without making contact therewith. This latter aspect has the advantage that the passage of the band-shaped substrate through a passage in a wall of the bath does not adversely affect the treatment of the band-shaped substrate with a liquid.

The device is preferably provided with a drip tray on the side of the passage remote from the interior of the bath.

In combination with such a drip tray, circulation means are furthermore preferably by which liquid that has found its way into the drip tray via a passage can be returned to the bath, so that the liquid can be utilised as efficiently as possible.

According to a very important preferred embodiment, the winding system is arranged for guiding the band-shaped substrate in a spiral path around the winding system with a number of windings, wherein the first pulley means and the second pulley means are arranged for guiding a number of windings spaced a pitch distance apart at a number of adjacent positions. Thus the treatment of a band-shaped substrate with a liquid can take place in a very compact manner, whilst the stresses that occur in the band-shaped substrate are nevertheless minimal.

The angle α preferably ranges between 2 degrees and 30 degrees, wherein the optimum angle also depends on the material properties as well as the dimensions of the band-shaped substrate.

To reduce tensile stresses and the occurrence of slip in the band-shaped substrate as much as possible it is furthermore generally preferable if the first pulley means comprises a first pulley being rotatable about a first axis of rotation for each winding, wherein the respective first axes of rotation are coaxial. The use of a number of individual first pulleys has the important advantage that they need not have exactly the same angular velocity, so that there is no need to compensate any elongation of the band-shaped substrate that occurs when the band-shaped substrate slips over the first pulley means in the longitudinal direction of the band-shaped substrate.

Also with a view to achieving the above advantages it is furthermore preferable if the conveying means comprise drive means for rotatably driving a single first pulley, which single first pulley is furthermore preferably an outermost first pulley. When the first axis of rotation has an, at least substantially, vertical orientation, such an outermost first pulley is formed by the lowermost pulley or the uppermost pulley of first pulley means.

In particular if a band-shaped substrate is only treated with a liquid on one side, it is preferable if the band-shaped substrate makes contact with pulley means forming part of the winding system on only one side within the winding system. The side that is treated with a liquid is located on the outer side in that case, whilst the band-shaped substrate abuts against the pulley means of the winding system with the inner side. The outer side of the band-shaped substrate that has been treated with a liquid is not loaded by contact between the band-shaped substrate and a pulley means.

The advantages of the invention apply in particular with regard to the galvanic treatment of a band-shaped substrate. Within that framework, another preferred embodiment is characterised in that the bath is a galvanic bath.

The invention also relates to a combination of two successive devices according to the invention as described in the foregoing, wherein the band-shaped substrate moves in opposite directions, seen in the direction parallel to the first axes of rotation associated with the respective devices. In this way the band-shaped substrate can be fed to the first device within the combination in a feeding direction and be discharged from the second device of the combination in the second direction, wherein said first direction and said second direction are in line with each other, which renders the combination highly suitable for incorporation in a production line.

According to another aspect of the present invention, the invention provides a method for treating a band-shaped substrate with a liquid, comprising the steps of conveying the band-shaped substrate through a bath by means of a conveying system, which conveying system comprises a winding system for guiding the band-shaped substrate in a spiral path around the winding system with at least one winding, which winding system comprises first pulley means being rotatable about a first axis of rotation for guiding said at least one winding of the band-shaped substrate through a first angle of deflection around part of the circumference of the first pulley means, and second pulley means for guiding said at least one winding of the band-shaped substrate through a second angle of deflection around part of the circumference of the second pulley means, which second pulley means comprises a second pulley, which is rotatable about a second axis of rotation, for each winding, wherein the band-shaped substrate extends through the liquid in the bath over at

FIG. 6 is a sectional view along the line VI-VI in FIG. 5;

FIG. 7 shows a detail of FIG. 6;

FIG. 8 is a sectional view along the line VIII-VIII in FIG. 5;

FIG. 9 shows a detail of FIG. 8;

FIG. 10 shows a detail of FIG. 9; and

FIG. 11 is a view along the line XI-XI in FIG. 5.

FIGS. 1 a and 1 b schematically show a production line 1 for electrolytically/galvanically plating a flexible band-shaped substrate 2. The band-shaped substrate 2 is supplied to the production line 1 from the supply side 3 and discharged from the production line 1 at the discharge side 4 after being treated with an electrolytic liquid by the production line 1. At the supply side 3, the band-shaped substrate 2 may be unwound from a supply reel (not shown), for example, whilst the band-shaped substrate 2 is wound onto a storage reel (not shown) at the discharge side 2. The portions of the band-shaped substrate 2 at the supply side, at the discharge side and also in the centre of the production line 1, indicated at 9, are in line with each other. The orientation of the band-shaped substrate 2 is such that the transverse direction of the band-shaped substrate 2 extends in vertical direction at the location of the supply-side 3 and the discharge side 4.

The production line 1 comprises four successive galvanic production units, which may each be considered as being a preferred embodiment of a device according to the invention. The first two production units 5, 6 are preferred embodiments of a first type of the device, whilst the last two production units 7, 8 are preferred embodiments of a second type. The first type of production units 5, 6 and the second type of production units 7, 8 will be discussed in more detail hereinafter with reference to FIGS. 2, 3 and FIGS. 4-11, respectively.

The production unit 5 includes a winding system 11 comprising a first pulley means 12 and a second pulley means 13. The first pulley means 12 comprises five first pulleys 14 having the same diameter D1, whose central axes are oriented co-axially and vertically. The second pulley means 13 comprises five second pulleys 15, which likewise have the same diameter D2. As FIG. 3 shows, the second pulleys 15 are arranged directly above each other, but they each have a central axis 16 which makes an angle α with the vertical. The central axes 16 associated with the five second pulleys 15 extend parallel to each other. The second pulleys 5 are freely rotatable about their central axes 16, to which end the second pulleys 15 are rotatably mounted on a fixedly disposed hub member 19, which has a vertical central axis.

The band-shaped substrate 2 is alternately passed over a pulley 14, 15 of the first pulley means 12 and the second pulley means 13, respectively, the deflection angle around the first pulleys 14 as well as around the second pulleys 15 being 180 degrees. The relative positions of the pulleys 14 and 15 have been selected so that the position at which the deflection angle starts at the point of entry 21 (FIG. 1 c) on a second pulley 15 is located at the same vertical level as the position at which the band-shaped substrate 2 leaves the pulley 14. The angle α as well as the diameter D2 have furthermore been selected so (D2=D1/cos(α)) that, given the aforesaid deflection angles, the exit point 22 at the end of the deflection angle of the second pulley 15 is located at the same vertical level as the pulley 14 (14′ in FIG. 1 c) positioned thereabove. As a result, the band-shaped substrate 2, insofar as it extends between the successive pulleys 14, 15, will only twist through an angle α about the neutral line of the band-shaped substrate, but said neutral line will continue to extend exactly horizontally. The magnitude of the angle α is 3 degrees in the present preferred embodiment. The optimum angle depends in part on the material properties and the dimensions of the band-shaped substrate 2. Precisely because of the fact that the deflection angle for the second pulleys 15 is 180 degrees, the band-shaped substrate 2, in spite of the oblique orientation of the second pulleys 15, will not only approach the second pulley 15 exactly in horizontal direction but also leave the second pulley 15 exactly in horizontal direction after being deflected 180 degrees.

An important advantage of the selection of the dimensions and orientation as described above is that the band-shaped substrate, apart from being slightly loaded in tension in the longitudinal direction of the band-shaped substrate 2, is only loaded in torsion between the pulleys 14, 15. More specifically, no forces act in transverse direction in the plane of the band-shaped substrate 2, which forces might cause the band-shaped substrate 2 to move in its plane perpendicular to the longitudinal direction of the band-shaped substrate 2 over the pulleys 14, 15, which leads to a highly stable guidance of the band-shaped substrate 2 and which significantly reduces or even excludes any tendency to wrinkle.

Drive means 25 are provided under the first pulley means 12 for driving the band-shaped substrate 2, which drive means only rotate the uppermost pulley 14 of the first pulley means 12. The other pulleys 14, 15 are on the one hand pulled along, as it were, by the band-shaped substrate 2, which is passed over the respective pulleys 14, 15 with some tension, and on the other hand they are driven by the limited friction between the pulleys 14, 15. Because of the inevitable elongation of the band-shaped substrate 2, the various pulleys 14, 15 will not move at the same angular velocity, so that in principle there need not be any slip between the band-shaped substrate 2 and the respective pulleys 14, 15. Such slip does occur between adjacent pulleys 14, 15, therefore, albeit to a very limited extent.

FIG. 2 shows the way in which the winding system 5 is accomodated in a box-like container 27, in the end faces of which openings 28, 29 are provided at the supply side 3 and the discharge side 4, respectively, to enable the band-shaped substrate 2 to pass through said openings 28, 29, wherein the band-shaped substrate 2 extends in the same vertical plane in the openings 28, 29, but wherein the band-shaped substrate 2 is located at a higher level in opening 29 than in opening 28. As those skilled in the art will appreciate upon viewing FIG. 1 b, this difference in height is fully eliminated again in the production unit 6.

An electrolytic bath 30 is provided halfway the length of the box-like container 27, between the pulley means 12, 13, in which bath, in use, an electrolytic liquid is present to a level 31 located above the upper side of the uppermost winding of the band-shaped substrate 2. Passages 34, 35 and 36, 37 are provided in the end walls 32, 33 of the bath 30, which passages have a greater width in FIG. 2 than will be desirable in practice. In practice the width of the passages 34-37 will be selected so that the band-shaped substrate 2 can just pass through the passages 34-37 without coming into contact therewith.

Drip trays 38, 39 are provided between the walls 32, 33 and the first pulley means 12 and the second pulley means 13, respectively, for receiving liquid from the bath 30 that leaks therefrom via the passages 34-37. Said liquid is returned to the bath 30 by circulation means (not shown).

Blowing means 40, 41 are provided in the drip trays 38, 39, at the location of the passages 34 and 37, i.e. where the band-shaped substrate 2 leaves the bath 30, for blow-drying the band-shaped substrate 2 on either side thereof, so that said band-shaped substrate 2 will make contact with one of the first pulleys 14 or second pulleys 15 in dry, or at least somewhat dry, condition.

It will be apparent to those skilled in the art that, using the production unit 5 in a very compact device, it is possible to deposit a layer electrochemically on either side of the band-shaped substrate 2 in the bath 30 at a high production rate. The electrolytic process is sufficiently well-known to those skilled in the art and requires no further explanation, therefore. It is only noted, unnecessarily, that an anodic material may be present in the bath 30, which is to dissolve in the liquid of the bath and precipitate on the sides on the band-shaped substrate 2. Alternatively, the anodic material may also be dissolved outside the bath 30. To stimulate the precipitation of the anodic material, a negative voltage is applied to the band-shaped substrate 2 via contact means (not shown), which may form part of the pulleys 14, 15, for example.

The production unit 6 is largely similar to the production unit 5, with this difference that the vertical change in the path of travel of the band-shaped substrate 2 takes place in opposite directions in the respective production units 5, 6, which is the reason why only the lowermost pulley 14 of the first pulley means 12 is driven in the production unit 6 instead of the uppermost pulley 14, as is the case in the production unit 5.

FIGS. 4-11 show a production unit 7 according to the second preferred embodiment in more detail. In view of the great similarity of the production units 7, 8, it will hardly be necessary, if at all, to explain the production unit 8 to the skilled person who has studied the description of the production unit 7.

The production unit 7 comprises a winding system 51 comprising first pulley means 52, second pulley means 53 and third pulley means 54. The first pulley means 52 is comparable to the first pulley means 12 of the production unit 5, in the sense that it comprises a number of first pulleys 55 whose central axes are oriented co-axially and vertically. Only the uppermost pulley 55 is rotatably driven by the driving motor 56.

The second pulley means 53 and the third pulley means 54 in turn are each comparable to the second pulley means 13 of production unit 5, in the sense that they each comprise a number of second pulleys 57 and third pulleys 58, respectively, which are arranged directly above each other for each pulley means 53, 54. The central axes associated with the second pulleys 57 and the third pulleys 58 each make an angle α of about 3 degrees with the vertical and extend parallel to each other. The second pulleys 57 and the third pulleys 58 are so positioned relative to each other that, in the view of FIG. 11, the respective pulleys 57, 58 are in line with each other. The pulleys 57, 58 are further provided with contact means (not shown) for applying a negative voltage to the band-shaped substrate 2 so as to advance the plating process.

The band-shaped substrate 2 is alternately passed over the pulleys 55, 57, 58 of the respective pulley means 52, 53, 54, with the angle of deflection around the first pulleys 55 being 180 degrees and the angle of deflection both around the second pulleys 57 and a round the third pulleys 58 being 90 degrees. Added together, the angles of deflection of the second pulleys 57 and the third pulleys 58 amount to 180 degrees, therefore.

The relative positions of the pulleys 55 and 57 have been selected so that the (neutral line of the) band-shaped substrate 2, insofar as it extends between successive pulleys 55, 57, extends exactly horizontally and only twists about the angle α within that range. Because the successive pulleys 57 and 58 are in line with each other (FIG. 11) and the respective angles of deflection are 90 degrees, the band-shaped substrate 2 slopes upwards (without any torsion) between the pulleys 57, 58, and subsequently leaves the pulleys 58 in exactly horizontal direction again at the end of the angle of deflection of 90 degrees of the pulleys 58. In fact the pulleys 57, 58 jointly have the same function as the pulleys 15 associated with the production unit 5, therefore, viz. moving the band-shaped substrate 2 to a higher (or, for the production units 6, 8, a lower) level, so as to thus form a next winding, without setting up any transverse forces in the band-shaped substrate 2. The advantage of the use of two pulley means 53, 54 in comparison with the use of one pulley means 13 is in particular the limited amount of space that the use of the two pulley means 53, 54 requires.

The winding system 51 is accommodated in a square box-like container 71. Openings 61 (FIG. 6), 62 (FIG. 4) are provided in line with each other in two opposite walls of the box-like container 71 to allow the band-shaped substrate 2 to pass therethrough. An at least substantially C-shaped bath 72 is provided within the container 71, on the outer side of a part of the angle of deflection of 180 degrees for the first pulleys 55, in the centre thereof. The outer side of the first pulley means 52 forms part of the upright wall of the C-shaped bath 72 on the inner side thereof, whilst the part of the wall of the bath 72 on the outer side of the C-shape is indicated by reference numeral 73. The circumference of the bath 72 is furthermore defined by end face walls 74, which extend outwards from the first pulley means 52 and which join the outer wall 73.

In the bath 72 an anode basket 75 is provided for holding anodic material, for example in the form of balls. Said anodic material is anodically connected via anode connections 76. In use, the bath 72 is filled with an electrolytic liquid to a level higher than that of the uppermost winding of the band-shaped substrate 2. In the bath 72, curved, horizontally oriented screening strips 77 extending along the larger part of the length of the bath 72 are furthermore provided at a comparatively short distance from the outer sides of the pulleys 55, at the location of the transitions therebetween, through which screening strips field lines can pass.

As in particular FIGS. 7, 9, 10 show, the first pulleys 55 are circumferentially provided with grooves 79, whose bottoms are made up of an elastic, strip-shaped masking body 80, which extends along the entire circumference of the groove 79. The masking bodies 80 are made of rubber, for example. The width of the grooves 79 is just a little greater than the width of the band-shaped substrate 2, as a result of which a gap 81 having a width of about 0.3 mm is present between the upright walls of the grooves 79 and the longitudinal edges of the band-shaped substrate 2. The side of the masking body 80 against which the band-shaped substrate 2 abuts comprises an upwardly sloping portion 82 (see FIG. 10) at the longitudinal edges thereof, which portion begins just within the width of the band-shaped substrate 2, thus ensuring a proper abutment of the band-shaped substrate 2 against the masking body 80, as a result of which the electrolytic treatment of the band-shaped substrate 2, which band-shaped substrate 2 is considerably thicker in FIGS. 7, 9, 10 than in actual practice, will only take place on the outer side of the band-shaped substrate 2.

On the side remote from the bath 72, the production unit 7 is provided with drip trays 91, which in fact form a common drip tray under the first pulley means 52. Said drip tray functions to receive liquid from the bath 72 which escapes from the bath 72 via the gap between the inwardly oriented ends of the end face walls 74 and the outer sides of the first pulley means 52. Said liquid is pumped back to the bath 72 by a circulation means (not shown).

Closing plates 83 are provided on the outer side of the first pulley means 52, both at the sections shown in FIGS. 8, 9 and 10 and near the end face walls 74, through which the band-shaped substrate 2 can just pass without making contact therewith. The sealing plates are provided with projections 84 which extend into the grooves 79. The sealing plates 83 are dimensioned and positioned in such a manner that a small gap is present between the first pulley means 52 including the band-shaped substrate 2 on the one hand and the sealing plates 83 on the other hand. The sealing plates 83 near the end face walls 74 are intended to reduce leakage from the bath 72, whilst the sealing plates 83 shown in FIGS. 8, 9, 10 are rather intended to prevent splash liquid from passing said seals from the drip trays 91.

The skilled person, having perused the above description of the production unit number 7 will also understand the operation and the construction of the production unit 8. Within the production unit 8, the band-shaped substrate 2 returns to the same the vertical level as the level at which the band-shaped substrate 2 approaches the production unit 7. In the production unit 8, the lowermost first pulley 55 is rotatably driven instead of the uppermost first pulley 55.

As those skilled in the art will appreciate, the invention is not limited to the preferred embodiments of the present invention as described in the foregoing, but the scope of the invention is in the first place determined by the appended claims. Alternatively it is also possible within the framework of the invention, for example, to use first, second and possibly third pulley means whose associated axes of rotation are oriented horizontally instead of (substantially) vertically. The second axis (axes) of rotation and possibly the third axis (axes) of rotation include an angle with the first axis of rotation, seen in top plan view, with the second pulley means and possibly the third pulley means preferably being provided above the first pulley means. Although a winding system around which the band-shaped substrate is guided in a spiral path with a number of windings is consistently mentioned in the above description of the preferred embodiments, it is alternatively also quite possible within the framework of the present invention to use a winding system around which the band-shaped substrate is guided in a spiral path with only one winding, for example (but not exclusively) for passing the band-shaped substrate through a rinsing bath. 

1. A device for treating a band-shaped substrate with a liquid, said device comprising: a conveying system for conveying the band-shaped substrate, which conveying system comprises a winding system for guiding the band-shaped substrate in a spiral path around the winding system with at least one winding, which winding system comprises first pulley means being rotatable about a first axis of rotation for guiding said at least one winding of the band-shaped substrate through a first angle of deflection around part of the circumference of the first pulley means, and second pulley means for guiding said at least one winding of the band-shaped substrate through a second angle of deflection around part of the circumference of the second pulley means, which second pulley means comprises a second pulley, which is rotatable about a second axis of rotation, for each winding; and a bath of the liquid, wherein the band-shaped substrate extends through the liquid in the bath over at least part of the length of said at least one winding, wherein the second axis of rotation of each second pulley makes an angle α with the first axis of rotation.
 2. A device according to claim 1, wherein the second pulley means have a number of second pulleys.
 3. A device according to claim 2, wherein the second pulleys have equal diameters.
 4. A device according to claim 1, wherein the second axes of rotation associated with the respective second pulleys extend parallel to each other.
 5. A device according to claim 1, wherein the first pulley means has a first diameter D1 at the location where said at least one winding is guided by the first pulley means and each second pulley has a second diameter D2 at the associated location where a winding is guided by the second pulley, wherein the second diameter D2 is larger than the first diameter D1.
 6. A device according to claim 5, wherein the dimension of the second diameter D2 is equal to that of the first diameter D1 divided by cos(α).
 7. A device according to claim 1, wherein both the first angle of deflection and the second angle of deflection equal 180 degrees.
 8. A device according to claim 1, wherein the winding system comprises third pulley means for guiding said at least one winding of the band-shaped substrate through a third angle of deflection around part of the circumference of the third pulley means, said third pulley means comprising a third pulley for each winding, which is rotatable about a third axis of rotation, each third pulley extending parallel to an associated second pulley.
 9. A device according to claim 8, wherein the sum of the second angle of deflection and the third angle of deflection equals 180 degrees.
 10. A device according to claim 8, wherein the second pulley means and the third pulley means are spaced from the first pulley means by the same distance.
 11. A device according to claim 1, wherein said bath is provided between the first pulley means and the second pulley means.
 12. A device according to claim 1, wherein the bath extends along part of the first angle of deflection on the outer side of the first pulley means.
 13. A device according to claim 12, wherein the first pulley means forms a mask in the bath for the side of the band-shaped substrate that faces towards the first pulley means so that the band-shaped substrate will be treated with the liquid only on the side remote from the first pulley means.
 14. A device according to claim 12, wherein the first pulley means comprises a contact surface for each winding, which contact surface slopes upwards at the longitudinal edges of the band-shaped substrate.
 15. A device according to claim 12, wherein the first pulley means comprises a groove having a bottom and two upright edges joining said bottom for each winding, wherein the band-shaped substrate abuts against the bottom and wherein the longitudinal edges of the band-shaped substrate preferably do not make contact with the upright edges.
 16. A device according to claim 15, wherein a clearance of maximally 1 mm is present between the longitudinal edges of the band-shaped substrate and the upright edges of the groove.
 17. A device according to claim 1, wherein the first axis of rotation has a vertical orientation or an orientation which deviates maximally 10 degrees therefrom.
 18. A device according to claim 1, wherein the first axis of rotation has a horizontal orientation.
 19. A device according to claim 1, wherein at least one passage through which the band-shaped substrate can pass is provided in at least one wall of the bath.
 20. A device according to claim 19, wherein said passage is arranged for allowing the band-shaped substrate to pass without making contact therewith.
 21. A device according to claim 19, wherein a drip tray is provided on the side of the passage remote from the interior of the bath.
 22. A device according to claim 21, wherein circulation means are provided, by which liquid that has found its way into the drip tray via a passage can be returned to the bath.
 23. A device according to claim 1, wherein the winding system is arranged for guiding the band-shaped substrate in a spiral path around the winding system with a number of windings, wherein the first pulley means and the second pulley means are arranged for guiding a number of windings spaced a pitch distance apart at a number of adjacent positions.
 24. A device according to claim 1, wherein the angle α ranges between 2 degrees and 30 degrees.
 25. A device according to claim 1, wherein the first pulley means comprises a first pulley being rotatable about a first axis of rotation for each winding, wherein the respective first axes of rotation are coaxial.
 26. A device according to claim 25, wherein the conveying means comprise drive means for rotatably driving a single first pulley.
 27. A device according to claim 26, wherein said single first pulley is an outermost first pulley.
 28. A device according to claim 1, wherein the band-shaped substrate makes contact with pulley means forming part of the winding system on only one side within the winding system.
 29. A device according to claim 1, wherein said bath is a galvanic bath.
 30. A combination of two successive devices according to claim 1, wherein the band-shaped substrate moves in opposite directions, seen in the direction parallel to the first axes of rotation associated with the respective devices.
 31. A method for treating a band-shaped substrate with a liquid, comprising: conveying the band-shaped substrate through a bath by means of a conveying system, which conveying system comprises a winding system for guiding the band-shaped substrate in a spiral path around the winding system with at least one winding, which winding system comprises first pulley means being rotatable about a first axis of rotation for guiding said at least one winding of the band-shaped substrate through a first angle of deflection around part of the circumference of the first pulley means, and second pulley means for guiding said at least one winding of the band-shaped substrate through a second angle of deflection around part of the circumference of the second pulley means, which second pulley means comprises a second pulley, which is rotatable about a second axis of rotation, for each winding, wherein the band-shaped substrate extends through the liquid in the bath over at least part of the length of a number of windings, wherein the second axis of rotation of each second pulley makes an angle α with the first axis of rotation.
 32. A method according to claim 31, wherein the band-shaped substrate is guided in a spiral path around the winding system with a number of windings.
 33. A method according to claim 32, wherein the band-shaped substrate is treated galvanically.
 34. A method according to claim 32, wherein the band-shaped substrate is made of stainless steel or copper,
 35. A method according to claim 32, wherein indium, selenium or gallium is deposited on the band-shaped substrate in the bath.
 36. A method according to claim 32, wherein the band-shaped substrate moves through the bath at a velocity of at least 2 metres per minute. 